Due to a process deviation, a threshold voltage Vth of a Thin Film Transistor (TFT) on an Active Matrix/Organic Light Emitting Diode (AMOLED) may shift, leading to non-uniform currents in different pixels. A conventional pixel driving circuit with a threshold compensation function may charge a storage capacitor by a voltage Vdata of a data signal on a data line during a pre-charging period, compensate the threshold by discharging the storage capacitor during a compensating period, and activate an Organic Light Emitting Diode (OLED) to emit light during a light-emitting period. However, such arrangement causes a complicated configuration, and a high quantity of control signals, so that an interval between adjacent pixels is narrow.